What common adverse effect should a patient taking nitroglycerin be taught about?

A common adverse effect that patients taking nitroglycerin should be educated about is dizziness. Nitroglycerin works by dilating blood vessels, which can lead to a drop in blood pressure, especially when standing up quickly. This drop in blood pressure can result in feelings of light-headedness or dizziness. Patients need to be aware of this possibility, particularly when they first start the medication or if their dosage is adjusted. It is crucial for patients to sit or lie down if they begin to feel dizzy, as this can help prevent falls and other complications associated with sudden changes in posture.

While headaches can also be experienced due to the vasodilatory effects of nitroglycerin, dizziness is often more prevalent and directly relates to the cardiovascular changes induced by the medication. Patients should be informed of the signs and symptoms they might encounter and given advice on how to manage them effectively.